diff --git a/tests/integration/Models/CustomFieldTest.php b/tests/integration/Models/CustomFieldTest.php
index 4dfc87112d..601066764b 100644
--- a/tests/integration/Models/CustomFieldTest.php
+++ b/tests/integration/Models/CustomFieldTest.php
@@ -85,17 +85,19 @@ class CustomFieldTest extends \MailPoetTest {
 
   public function testItHasACreatedAtOnCreation() {
     $customField = CustomField::findOne($this->customField->id);
+    assert($customField instanceof CustomField);
     expect($customField->createdAt)->notNull();
   }
 
   public function testItHasAnUpdatedAtOnCreation() {
     $customField = CustomField::findOne($this->customField->id);
-    expect($customField->updatedAt)
-      ->equals($customField->createdAt);
+    assert($customField instanceof CustomField);
+    expect($customField->updatedAt)->equals($customField->createdAt);
   }
 
   public function testItUpdatesTheUpdatedAtOnUpdate() {
     $customField = CustomField::findOne($this->customField->id);
+    assert($customField instanceof CustomField);
     $createdAt = $customField->createdAt;
 
     sleep(1);
@@ -104,6 +106,7 @@ class CustomFieldTest extends \MailPoetTest {
     $customField->save();
 
     $updatedCustomField = CustomField::findOne($customField->id);
+    assert($updatedCustomField instanceof CustomField);
     expect($updatedCustomField->createdAt)->equals($createdAt);
     $isTimeUpdated = (
       $updatedCustomField->updatedAt > $updatedCustomField->createdAt
@@ -122,6 +125,7 @@ class CustomFieldTest extends \MailPoetTest {
       $association->save();
     }
     $customField = CustomField::findOne($this->customField->id);
+    assert($customField instanceof CustomField);
     $subscribers = $customField->subscribers()->findArray();
     expect(count($subscribers))->equals(2);
   }
@@ -135,6 +139,7 @@ class CustomFieldTest extends \MailPoetTest {
     $association->value = '12/12/2012';
     $association->save();
     $customField = CustomField::findOne($this->customField->id);
+    assert($customField instanceof CustomField);
     $subscriber = $customField->subscribers()->findOne();
     expect($subscriber->value)->equals($association->value);
   }
diff --git a/tests/integration/Models/FormTest.php b/tests/integration/Models/FormTest.php
index 9d2a953c52..03473fb310 100644
--- a/tests/integration/Models/FormTest.php
+++ b/tests/integration/Models/FormTest.php
@@ -44,22 +44,25 @@ class FormTest extends \MailPoetTest {
 
   public function testItCanBeSearched() {
     $form = Form::filter('search', 'my F')->findOne();
+    assert($form instanceof Form);
     expect($form->name)->equals('My Form');
   }
 
   public function testItHasACreatedAtOnCreation() {
     $form = Form::findOne($this->form->id);
+    assert($form instanceof Form);
     expect($form->createdAt)->notNull();
   }
 
   public function testItHasAnUpdatedAtOnCreation() {
     $form = Form::findOne($this->form->id);
-    expect($form->updatedAt)
-      ->equals($form->createdAt);
+    assert($form instanceof Form);
+    expect($form->updatedAt)->equals($form->createdAt);
   }
 
   public function testItUpdatesTheUpdatedAtOnUpdate() {
     $form = Form::findOne($this->form->id);
+    assert($form instanceof Form);
     $createdAt = $form->createdAt;
 
     sleep(1);
@@ -68,6 +71,7 @@ class FormTest extends \MailPoetTest {
     $form->save();
 
     $updatedForm = Form::findOne($form->id);
+    assert($updatedForm instanceof Form);
     expect($updatedForm->createdAt)->equals($createdAt);
     $isTimeUpdated = (
       $updatedForm->updatedAt > $updatedForm->createdAt
@@ -83,6 +87,7 @@ class FormTest extends \MailPoetTest {
     expect($createdForm->getErrors())->false();
 
     $form = Form::findOne($createdForm->id);
+    assert($form instanceof Form);
     expect($form->name)->equals('Created Form');
 
     $isUpdated = Form::createOrUpdate([
@@ -90,6 +95,7 @@ class FormTest extends \MailPoetTest {
       'name' => 'Updated Form',
     ]);
     $form = Form::findOne($createdForm->id);
+    assert($form instanceof Form);
     expect($form->name)->equals('Updated Form');
   }
 
@@ -148,8 +154,12 @@ class FormTest extends \MailPoetTest {
     ]);
     $this->settings->set('signup_confirmation.enabled', '0');
     Form::updateSuccessMessages();
-    $default = Form::findOne($default->id)->asArray();
-    $custom = Form::findOne($custom->id)->asArray();
+    $default = Form::findOne($default->id);
+    $custom = Form::findOne($custom->id);
+    assert($default instanceof Form);
+    assert($custom instanceof Form);
+    $default = $default->asArray();
+    $custom = $custom->asArray();
     expect($default['settings']['success_message'])->equals('You’ve been successfully subscribed to our newsletter!');
     expect($custom['settings']['success_message'])->equals('Thanks for joining us!');
   }
@@ -165,8 +175,12 @@ class FormTest extends \MailPoetTest {
     ]);
     $this->settings->set('signup_confirmation.enabled', '1');
     Form::updateSuccessMessages();
-    $default = Form::findOne($default->id)->asArray();
-    $custom = Form::findOne($custom->id)->asArray();
+    $default = Form::findOne($default->id);
+    $custom = Form::findOne($custom->id);
+    assert($default instanceof Form);
+    assert($custom instanceof Form);
+    $default = $default->asArray();
+    $custom = $custom->asArray();
     expect($default['settings']['success_message'])->equals('Check your inbox or spam folder to confirm your subscription.');
     expect($custom['settings']['success_message'])->equals('Thanks for joining us!');
   }
diff --git a/tests/integration/Models/NewsletterOptionFieldTest.php b/tests/integration/Models/NewsletterOptionFieldTest.php
index 3e09c2c248..f0fc50c052 100644
--- a/tests/integration/Models/NewsletterOptionFieldTest.php
+++ b/tests/integration/Models/NewsletterOptionFieldTest.php
@@ -69,12 +69,13 @@ class NewsletterOptionFieldTest extends \MailPoetTest {
 
   public function testItHasAnUpdatedAtOnCreation() {
     $optionField = NewsletterOptionField::findOne($this->optionField->id);
-    expect($optionField->updatedAt)
-      ->equals($optionField->createdAt);
+    assert($optionField instanceof NewsletterOptionField);
+    expect($optionField->updatedAt)->equals($optionField->createdAt);
   }
 
   public function testItUpdatesTheUpdatedAtOnUpdate() {
     $optionField = NewsletterOptionField::findOne($this->optionField->id);
+    assert($optionField instanceof NewsletterOptionField);
     $createdAt = $optionField->createdAt;
 
     sleep(1);
@@ -83,6 +84,7 @@ class NewsletterOptionFieldTest extends \MailPoetTest {
     $optionField->save();
 
     $updatedOptionField = NewsletterOptionField::findOne($optionField->id);
+    assert($updatedOptionField instanceof NewsletterOptionField);
     $isTimeUpdated = (
       $updatedOptionField->updatedAt > $updatedOptionField->createdAt
     );
@@ -100,6 +102,7 @@ class NewsletterOptionFieldTest extends \MailPoetTest {
       $association->save();
     }
     $optionField = NewsletterOptionField::findOne($this->optionField->id);
+    assert($optionField instanceof NewsletterOptionField);
     $newsletters = $optionField->newsletters()
       ->findArray();
     expect(count($newsletters))->equals(2);
@@ -115,6 +118,7 @@ class NewsletterOptionFieldTest extends \MailPoetTest {
     $association->value = 'list';
     $association->save();
     $optionField = NewsletterOptionField::findOne($this->optionField->id);
+    assert($optionField instanceof NewsletterOptionField);
     $newsletter = $optionField->newsletters()
       ->findOne();
     expect($newsletter->value)->equals($association->value);
diff --git a/tests/integration/Models/NewsletterOptionTest.php b/tests/integration/Models/NewsletterOptionTest.php
index 70feed4702..7562d97ffe 100644
--- a/tests/integration/Models/NewsletterOptionTest.php
+++ b/tests/integration/Models/NewsletterOptionTest.php
@@ -24,6 +24,7 @@ class NewsletterOptionTest extends \MailPoetTest {
     $newsletterOption = NewsletterOption::where('newsletter_id', $data['newsletter_id'])
       ->where('option_field_id', $data['option_field_id'])
       ->findOne();
+    assert($newsletterOption instanceof NewsletterOption);
     expect($newsletterOption->value)->equals($data['value']);
 
     // it can update
@@ -32,6 +33,7 @@ class NewsletterOptionTest extends \MailPoetTest {
     $newsletterOption = NewsletterOption::where('newsletter_id', $data['newsletter_id'])
       ->where('option_field_id', $data['option_field_id'])
       ->findOne();
+    assert($newsletterOption instanceof NewsletterOption);
     expect($newsletterOption->value)->equals($data['value']);
   }
 
diff --git a/tests/integration/Models/NewsletterTest.php b/tests/integration/Models/NewsletterTest.php
index b000156212..334b8053e6 100644
--- a/tests/integration/Models/NewsletterTest.php
+++ b/tests/integration/Models/NewsletterTest.php
@@ -62,33 +62,38 @@ class NewsletterTest extends \MailPoetTest {
 
   public function testItHasASubject() {
     $newsletter = Newsletter::findOne($this->newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->subject)->equals($this->newsletter->subject);
   }
 
   public function testItHasAType() {
     $newsletter = Newsletter::findOne($this->newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->type)->equals($this->newsletter->type);
   }
 
   public function testItHasABody() {
     $newsletter = Newsletter::findOne($this->newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->body)->equals($this->newsletter->body);
   }
 
   public function testItHasPreheader() {
     $newsletter = Newsletter::findOne($this->newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->preheader)->equals($this->newsletter->preheader);
   }
 
   public function testItHasACreatedAtOnCreation() {
     $newsletter = Newsletter::findOne($this->newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->createdAt)->notNull();
   }
 
   public function testItHasAnUpdatedAtOnCreation() {
     $newsletter = Newsletter::findOne($this->newsletter->id);
-    expect($newsletter->updatedAt)
-      ->equals($newsletter->createdAt);
+    assert($newsletter instanceof Newsletter);
+    expect($newsletter->updatedAt)->equals($newsletter->createdAt);
   }
 
   public function testItUpdatesTheUpdatedAtOnUpdate() {
@@ -102,6 +107,7 @@ class NewsletterTest extends \MailPoetTest {
     $newsletter->save();
 
     $updatedNewsletter = Newsletter::findOne($newsletter->id);
+    assert($updatedNewsletter instanceof Newsletter);
     expect($updatedNewsletter->createdAt)->equals($createdAt);
     $isTimeUpdated = (
       $updatedNewsletter->updatedAt > $updatedNewsletter->createdAt
@@ -160,6 +166,7 @@ class NewsletterTest extends \MailPoetTest {
 
     $newsletter = Newsletter::where('subject', 'new newsletter')
       ->findOne();
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->subject)->equals('new newsletter');
 
     $isUpdated = Newsletter::createOrUpdate(
@@ -168,6 +175,7 @@ class NewsletterTest extends \MailPoetTest {
         'subject' => 'updated newsletter',
       ]);
     $newsletter = Newsletter::findOne($newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->subject)->equals('updated newsletter');
   }
 
@@ -192,6 +200,7 @@ class NewsletterTest extends \MailPoetTest {
     $association->save();
     $newsletter = Newsletter::filter('filterWithOptions', Newsletter::TYPE_WELCOME)
       ->findOne($this->newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->event)->equals($association->value);
   }
 
@@ -548,6 +557,7 @@ class NewsletterTest extends \MailPoetTest {
 
     // if meta option exists, it should be returned as an array
     $newsletter = Newsletter::filter('filterWithOptions', Newsletter::TYPE_AUTOMATIC)->findOne($newsletter->id);
+    assert($newsletter instanceof Newsletter);
     expect($newsletter->getMeta())->equals($meta);
   }
 
@@ -564,6 +574,7 @@ class NewsletterTest extends \MailPoetTest {
       ]);
       $newsletter->setStatus(Newsletter::STATUS_DRAFT);
       $taskFound = ScheduledTask::findOne($task->id());
+      assert($taskFound instanceof ScheduledTask);
       expect($taskFound->status)->equals(ScheduledTask::STATUS_PAUSED);
     }
   }
@@ -585,6 +596,7 @@ class NewsletterTest extends \MailPoetTest {
       ]);
       $newsletter->setStatus(Newsletter::STATUS_ACTIVE);
       $taskFound = ScheduledTask::findOne($task->id());
+      assert($taskFound instanceof ScheduledTask);
       expect($taskFound->status)->equals(ScheduledTask::STATUS_SCHEDULED);
     }
   }
diff --git a/tests/integration/Models/ScheduledTaskTest.php b/tests/integration/Models/ScheduledTaskTest.php
index 3af025fc63..e241a10a04 100644
--- a/tests/integration/Models/ScheduledTaskTest.php
+++ b/tests/integration/Models/ScheduledTaskTest.php
@@ -70,12 +70,16 @@ class ScheduledTaskTest extends \MailPoetTest {
     ]);
     ScheduledTask::setScheduledAllByNewsletter($newsletter);
     $task1Found = ScheduledTask::findOne($task1->id());
+    assert($task1Found instanceof ScheduledTask);
     expect($task1Found->status)->equals(ScheduledTask::STATUS_SCHEDULED);
     $task2Found = ScheduledTask::findOne($task2->id());
+    assert($task2Found instanceof ScheduledTask);
     expect($task2Found->status)->equals(ScheduledTask::STATUS_COMPLETED);
     $task3Found = ScheduledTask::findOne($task3->id());
+    assert($task3Found instanceof ScheduledTask);
     expect($task3Found->status)->equals(ScheduledTask::STATUS_SCHEDULED);
     $outdatedTaskFound = ScheduledTask::findOne($outdatedTask->id());
+    assert($outdatedTaskFound instanceof ScheduledTask);
     expect($outdatedTaskFound->status)->equals(ScheduledTask::STATUS_PAUSED);
   }
 
@@ -99,8 +103,10 @@ class ScheduledTaskTest extends \MailPoetTest {
     ]);
     ScheduledTask::pauseAllByNewsletter($newsletter);
     $task1Found = ScheduledTask::findOne($task1->id());
+    assert($task1Found instanceof ScheduledTask);
     expect($task1Found->status)->equals(ScheduledTask::STATUS_COMPLETED);
     $task2Found = ScheduledTask::findOne($task2->id());
+    assert($task2Found instanceof ScheduledTask);
     expect($task2Found->status)->equals(ScheduledTask::STATUS_PAUSED);
   }
 
@@ -128,6 +134,7 @@ class ScheduledTaskTest extends \MailPoetTest {
 
   public function testItJsonEncodesMetaWhenSaving() {
     $task = ScheduledTask::create();
+    assert($task instanceof ScheduledTask);
     $meta = [
       'some' => 'value',
     ];
@@ -135,6 +142,7 @@ class ScheduledTaskTest extends \MailPoetTest {
     $task->save();
 
     $task = ScheduledTask::findOne($task->id);
+    assert($task instanceof ScheduledTask);
 
     /** @var string $taskMeta */
     $taskMeta = $task->meta;
@@ -149,6 +157,7 @@ class ScheduledTaskTest extends \MailPoetTest {
     $task->save();
 
     $task = ScheduledTask::findOne($task->id);
+    assert($task instanceof ScheduledTask);
 
     expect(Helpers::isJson($task->meta))->false();
     expect($task->meta)->equals($meta);
diff --git a/tests/integration/Models/SegmentTest.php b/tests/integration/Models/SegmentTest.php
index 991696387d..8cc44cfc54 100644
--- a/tests/integration/Models/SegmentTest.php
+++ b/tests/integration/Models/SegmentTest.php
@@ -98,17 +98,20 @@ class SegmentTest extends \MailPoetTest {
 
   public function testItHasACreatedAtOnCreation() {
     $segment = Segment::findOne($this->segment->id);
+    assert($segment instanceof Segment);
     expect($segment->createdAt)->notNull();
   }
 
   public function testItHasAnUpdatedAtOnCreation() {
     $segment = Segment::findOne($this->segment->id);
+    assert($segment instanceof Segment);
     expect($segment->updatedAt)
       ->equals($segment->createdAt);
   }
 
   public function testItUpdatesTheUpdatedAtOnUpdate() {
     $segment = Segment::findOne($this->segment->id);
+    assert($segment instanceof Segment);
     $createdAt = $segment->createdAt;
 
     sleep(1);
@@ -117,6 +120,7 @@ class SegmentTest extends \MailPoetTest {
     $segment->save();
 
     $updatedSegment = Segment::findOne($segment->id);
+    assert($updatedSegment instanceof Segment);
     expect($updatedSegment->createdAt)->equals($createdAt);
     $isTimeUpdated = (
       $updatedSegment->updatedAt > $updatedSegment->createdAt
@@ -133,6 +137,7 @@ class SegmentTest extends \MailPoetTest {
 
     $segment = Segment::where('name', 'new list')
       ->findOne();
+    assert($segment instanceof Segment);
     expect($segment->name)->equals('new list');
 
     $isUpdated = Segment::createOrUpdate(
@@ -142,6 +147,7 @@ class SegmentTest extends \MailPoetTest {
       ]);
     $segment = Segment::where('name', 'updated list')
       ->findOne();
+    assert($segment instanceof Segment);
     expect($segment->name)->equals('updated list');
   }
 
@@ -156,6 +162,7 @@ class SegmentTest extends \MailPoetTest {
       $association->save();
     }
     $segment = Segment::findOne($this->segment->id);
+    assert($segment instanceof Segment);
     $subscribers = $segment->subscribers()
       ->findArray();
 
@@ -173,6 +180,7 @@ class SegmentTest extends \MailPoetTest {
       $association->save();
     }
     $segment = Segment::findOne($this->segment->id);
+    assert($segment instanceof Segment);
     $newsletters = $segment->newsletters()
       ->findArray();
 
diff --git a/tests/integration/Models/SendingQueueTest.php b/tests/integration/Models/SendingQueueTest.php
index a7b51f7945..958d1a983a 100644
--- a/tests/integration/Models/SendingQueueTest.php
+++ b/tests/integration/Models/SendingQueueTest.php
@@ -75,6 +75,7 @@ class SendingQueueTest extends \MailPoetTest {
     $queue->save();
 
     $queue = SendingQueue::findOne($queue->id);
+    assert($queue instanceof SendingQueue);
 
     /** @var string queue_newsletter_rendered_body */
     $queueNewsletterRenderedBody = $queue->newsletterRenderedBody;
@@ -84,6 +85,7 @@ class SendingQueueTest extends \MailPoetTest {
 
   public function testItJsonEncodesMetaWhenSaving() {
     $queue = SendingQueue::create();
+    assert($queue instanceof SendingQueue);
     $meta = [
       'some' => 'value',
     ];
@@ -93,8 +95,10 @@ class SendingQueueTest extends \MailPoetTest {
     $queue->save();
 
     $queue = SendingQueue::findOne($queue->id);
+    assert($queue instanceof SendingQueue);
 
     expect(Helpers::isJson($queue->meta))->true();
+    assert(is_string($queue->meta));
     expect(json_decode((string)$queue->meta, true))->equals($meta);
   }
 
@@ -107,6 +111,7 @@ class SendingQueueTest extends \MailPoetTest {
     $queue->save();
 
     $queue = SendingQueue::findOne($queue->id);
+    assert($queue instanceof SendingQueue);
 
     expect(Helpers::isJson($queue->meta))->false();
     expect($queue->meta)->equals($meta);
@@ -125,11 +130,13 @@ class SendingQueueTest extends \MailPoetTest {
       ]
     );
     $sendingQueue = SendingQueue::findOne($queue->id);
+    assert($sendingQueue instanceof SendingQueue);
     expect($sendingQueue->newsletterRenderedBody)->equals(serialize($newsletterRenderedBody));
 
     // re-saving the queue will re-rencode the body using json_encode()
     $sendingQueue->save();
     $sendingQueue = SendingQueue::findOne($queue->id);
+    assert($sendingQueue instanceof SendingQueue);
     expect($sendingQueue->newsletterRenderedBody)->equals(json_encode($newsletterRenderedBody));
   }
 
diff --git a/tests/integration/Models/SubscriberSegmentTest.php b/tests/integration/Models/SubscriberSegmentTest.php
index 8e82d39ace..b327bc9e03 100644
--- a/tests/integration/Models/SubscriberSegmentTest.php
+++ b/tests/integration/Models/SubscriberSegmentTest.php
@@ -249,6 +249,7 @@ class SubscriberSegmentTest extends \MailPoetTest {
 
     // check that we have the proper status
     $created = SubscriberSegment::findOne($result->id);
+    assert($created instanceof SubscriberSegment);
     expect($created->status)->equals(Subscriber::STATUS_SUBSCRIBED);
 
     // update same combination of subscriber/segment with a different status
@@ -262,6 +263,7 @@ class SubscriberSegmentTest extends \MailPoetTest {
 
     // check updated status
     $updated = SubscriberSegment::findOne($created->id);
+    assert($updated instanceof SubscriberSegment);
     expect($updated->status)->equals(Subscriber::STATUS_UNSUBSCRIBED);
 
     // we should have only one relationship for that user